<?php
 
error_reporting(-1);
mb_internal_encoding('utf-8');
 
 
$text = "Аргентина манит негра";
$result = 'Это палиндром';
$resultN = "Это не палиндром";
 
mb_strtolower($text);
$text = str_replace(' ', '', $text);
 
$length = mb_strlen($text);
$halfLength = floor($length/ 2);
$new = $length;
 
for ($i = 0; $i <= $halfLength; $i++)  {
	$symbol = mb_substr($text, $i, $halfLength);
	$symbolRev = mb_substr($text, $length, $halfLength);
	if ($symbol == $symbolRev) {
   echo $result;
} else {
   echo $resultN;
}
}

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